Dataset Information

Comparative genome analysis of Alkalihalobacillus okhensis Kh10-101^T reveals insights into adaptive mechanisms for halo-alkali tolerance.

ABSTRACT: Alkalihalobacillus okhensis is a halo-alkaliphile with optimal growth at pH 10 and 5% NaCl. Phylogenetic analysis revealed habitat-dependent segregation of Bacilli, with all the alkalihalophiles forming a separate clade. It uses acidification of the external medium and pH-dependent cell wall reinforcement to survive sodic environments. Interestingly, comparative genome analysis revealed the genome encodes surface proteins with a high proportion of acidic amino acids compared to their orthologs of B. subtilis, a piece of direct evidence for adaptive evolution. It has a relatively higher number of genes involved in the metabolism of osmolytes and sodium-dependent transporters when compared to B. subtilis. Growth of Alkalihalobacillus okhensis strain Kh10-101^T (hereafter A. okhensis) is Na⁺ dependent, with a minimum of 4% NaCl at neutral pH, but 0.5% NaCl is enough at pH 10. It tolerated a sudden increase in salt concentration and exhibited an elongated phenotype but could not tolerate a sudden pH shift from 7 to 11. The cell envelope got damaged, confirming that the pH regulation through cell wall reinforcement is key to survival at a high-pH condition. We report for the first time a comprehensive genome analysis of Bacilli to delineate the mechanisms evolved for adaptation to halo-alkaline conditions.

Supplementary information

The online version contains supplementary material available at 10.1007/s13205-021-02938-x.

SUBMITTER: Krishna PS

PROVIDER: S-EPMC8325738 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Comparative genome analysis of Alkalihalobacillus okhensis Kh10-101 T reveals insights into adaptive mechanisms for halo-alkali tolerance.

Krishna Pilla Sankara PS Raghunathan Sarada S Prakash Jogadhenu S S JSS

3 Biotech 20210731 8

Alkalihalobacillus okhensis is a halo-alkaliphile with optimal growth at pH 10 and 5% NaCl. Phylogenetic analysis revealed habitat-dependent segregation of Bacilli, with all the alkalihalophiles forming a separate clade. It uses acidification of the external medium and pH-dependent cell wall reinforcement to survive sodic environments. Interestingly, comparative genome analysis revealed the genome encodes surface proteins with a high proportion of acidic amino acids compared to the ...[more]

PMID: 34350093

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Dataset Information

Comparative genome analysis of Alkalihalobacillus okhensis Kh10-101^T reveals insights into adaptive mechanisms for halo-alkali tolerance.

Supplementary information

Publications

Comparative genome analysis of <i>Alkalihalobacillus okhensis</i> Kh10-101<sup> T</sup> reveals insights into adaptive mechanisms for halo-alkali tolerance.

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